A fuel tank in a vehicle (such as aircrafts) is typically comprised of a rigid metal container to hold fuel for consumption by the vehicle. This container in an aircraft is typically accessible via a large metal tank access door secured to the aircraft. Some fuel tanks may have a flexible bladder internal to the metal container. However, such metal container and access door are typically heavy and are costly to manufacture and install. Additionally, high-performance aircrafts typically require pressurized fuel delivery for consumption to avoid cavitation, for example. This can be achieved by providing one or more pumps throughout the fuel line between the fuel tank and the engine(s) to provide externally pressurized fuel. Although there are applications of flexible bladders for use in externally pressurized fuel systems, to externally pressurize the bladder for fuel removal most applications rely on either a metallic fuel tank to act as a pressure vessel or they seal a portion of the surrounding structure to act as a pressure vessel—both at the expense of weight, cost and mechanical complexity.
Reference will now be made to the exemplary embodiments illustrated, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended.